Malan overgrowth syndrome
Findings
No curated finding names Malan overgrowth syndrome yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
A rare multisystemic genetic disorder characterized by a characteristic facial features with macrocephaly, overgrowth in infancy, intellectual disability and behavioral problems including anxieties and aggressiveness.
Definition from the Mondo Disease Ontology (MONDO:0013885), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal dominant inheritance
- Onset and course
- Neonatal onset · Childhood onset
HPO, annotations 2026-09-02
Features
58 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- AnxietyHPOHP:0000739
- 3 of 3 reported patients
- Occasional (5% to 29% of cases)
- Delayed speech and language developmentHPOHP:0000750
- 5 of 5 reported patients
- High foreheadHPOHP:0000348
- 5 of 5 reported patients
- Frequent (30% to 79% of cases)
- Intellectual disabilityHPOHP:0001249
- 5 of 5 reported patients
- MacrocephalyHPOHP:0000256
- 3 of 3 reported patients
- Frequent (30% to 79% of cases)
- OvergrowthHPOHP:0001548
- 3 of 3 reported patients
Show the remaining 46
- VentriculomegalyHPOHP:0002119
- 2 of 3 reported patients
- Frequent (30% to 79% of cases)
- Autistic behaviorHPOHP:0000729
- 3 of 5 reported patients
- Everted lower lip vermilionHPOHP:0000232
- 3 of 5 reported patients
- Feeding difficulties in infancyHPOHP:0008872
- Frequent (30% to 79% of cases)
- Hypoplasia of the corpus callosumHPOHP:0002079
- 1 of 3 reported patients
- Frequent (30% to 79% of cases)
- Low posterior hairlineHPOHP:0002162
Genes
1 gene
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- NFIXHGNC:7788
- Definitive · Ambry Genetics · Autosomal dominant · 2018
- Definitive · ClinGen · Autosomal dominant · 2023
- Definitive · Illumina · Autosomal dominant · 2019
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal dominant · 2023
- Strong · PanelApp Australia · Autosomal dominant · 2025
- Supportive · Orphanet · Autosomal dominant · 2021
Where it sits
Other names
3 names
Resolves to: Malan overgrowth syndrome
- Also called
- Malan syndromeSotos syndrome 2Sotos syndrome type 2